Return bend



Jupe14, 1938. F, E, Ky. 21,120,498

RETURN BND Filed Maron 2o, 1936 24 v l w Y L f- /a Y Z I 2 ginge/357%19/ www@ l Patented June 14, 1938 UNITED STATES PATENT OFFICE RETURNBEND Frederick E. Key, St. Louis, Mo., assignor, by mesne assignments,to Reconstruction Finance Corporation, St. Louis, Mo., a corporation ofthe United States o! America .Application March 20, 1936, Serial No.69,799

2 Claims.

An object of the invention is to provide a return bend of novelconstruction and formation, in combination with novel means forattaching the same to tubes so that the return bends may be mounted in.close assembly in oil stills, and may be conveniently detached from thetubes when occasion arises to detach them.

Another object of the invention is to provide novel attaching means forthe return bends whereby they may be conveniently attached to the tubesor detached from the tubes without damaging the attaching means.

Another object of the invention is to provide improved means forattaching return bends to tubes including collars adjustably mounted onthe tubes and provided with a plurality of thread- .ed holes adapted toreceive the ends of bolts provided with Acme threads on their inner endsand with conventional or S. A. E. threads on their outer ends, whichextend through holes in the return bend structure and have nuts screwedon said conventional or S.A. E. threads rigidly securingthe returnbendsi on the tubes. Thus, when the nuts freeze to the bolts, theybecome in effect bolt heads adapted to receive socket wrenches wherebythe Acme threaded end of the bolt maybe screwed out of the holes in thecollars and the return bend detached.

Other objects of the invention will be apparent from the followingdescription, reference be 'partly in side elevation and ends of the twotubes 2 and forms communica-l tion between them. -The ends of the returnbend have tapered sockets 3 and the end portions of -the tube havetapered walls 4 seating closelyl against the walls of the sockets 3 andcooperating therewith to form a leak-proof joint. The.

walls of the sockets and the walls` 4 of the tubes may be ground toassure close t. The tubes end at an abrupt wall 5 (Fig. 3) to which isrigidly attached a. ring 6 of stainless steel that will not erode orwear when in use and which has an outer inclined wall I in continuationof the wall 4 and'intersecting the inner wall of said ring at the outerend thereof to form an approximately sharp edge 8. y

lA collar 9 is screwed on threads L0 of the Acme type formed on eachtube 2 inwardly beyond the beveled wall 4. Each collar has there-lthrough, parallel with the axis of the tube on which it is mounted, anannular series of holes II having threadsv of the Acme type. 'I'he outerend of each collar has an annular ange I2 projecting therefrom andengaging in a socket I3 in the adjacent end of the return bend.

The return bend has outward extensions I4 provided with openings I5 inaxial alinement with the tubes and which openings, when the return bendis in use, are closed by removable and replaceable plugs I6, `for wellunderstood purposes. The inner ends of the return bend have radiallyextended portions I'I provided with holes I8 which may be brought intoaxial alinement with certain of the holes II. Since this device isprovided specially for close assembly, .I have formed channels I9 in theoutwardly extended portions I4 inward radially from the holes I8.

The attaching devices comprise bolts, each having on its inner end Acmethreads 2| and on its outer end conventional or S. A. E. threads 22between which two threads is an unthreaded portion 23.

In mounting the return bend on the tubes, the collars 9 are iirstscrewed onto the tubes beyond the tapered walls 4. The Acme threads 2|of a bolt are then screwed into each of the holes II with the exceptionof the hole II that is to-v ward the other 'tube or collar. Then thereturn bend is placed in position, the bolts passing through the holesI8 freely and the walls of the socket 3 seating closely against-theinclined walls 4 and 'I of the tube end portions. The outer threadedends of the bolts extend beyond the extended portions Il of the returnbend within the grooves I9. The nuts 24 are then screwed on the outerends of the bolts by means of a socket wrench which may be operatedwithin the grooves I9. The nuts are screwed into the clamping engagementwith the 'extensions Il, thereby rigidly securing the return bend inconnection with the tubes and 4forming leak-proof joints. When it isdesired to detach the return bend, it is unnecessary to destroy thebolts since they mayl be removed even if the nuts 24 have become frozento the bolts, since the Acme threads 2| will screw along the Acmethreadsin the ,holes Il with which they are engaged. After the boltshave been removed, the nuts 24 may be `detached therefrom by knownpractices without damaging the bolts, thus permitting the bolts to beused repeatedly, which cannot be done in any other modern U-bendstructures with which I am familiar.

A feature o( the invention consists of the fact that there is at leastone hole II more than the holes I8 in the adjacent ends of the U-bend.This permits more accurate adjustment of Athe parts and, in the specificform shown, it is necessary only to turn the collar 0 one-sixth of arevolution in order to aline the holes Il-with the holes I8.

It is now clear that the invention attains all of its objects andpurposes in a highly satisfactory manner. The construction, arrangementand relationship of the parts. may be varied within the scope ofequivalent limits without departure from the nature and principle of theinvention.

I claim:-

1. A return bend for connecting two tubes and having tapered sockets inits ends adapted to receive tapered ends of said tubes, tapered ringsattached to the ends -oi said tubes within said tapered sockets andcooperating with the walls oi said sockets to form leak-proof joints,and

means for attachingsaid return bend to said tubes to form leak-prooijoints by engagement of the walls of said tapered ends and said ringswith the walls of said sockets.

2. A return bend for connecting two tubes having tapered sockets in itsends adapted to receive tapered end portions of said tubes. nonerodibletapered rings attached to the ends of

